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71.
Samuel Luke Tunstall 《Teaching Statistics》2016,38(2):65-66
This paper describes a case study for introductory statistics courses that promotes critical thinking in relation to causation. 相似文献
72.
Pascal Wettstein Craig Priest Sameer A. Al-Bataineh Robert D. Short Paul M. Bryant James W. Bradley Suet P. Low Luke Parkinson Endre J. Szili 《Biomicrofluidics》2015,9(1)
Spatially varied surface treatment of a fluorescently labeled Bovine Serum Albumin (BSA) protein, on the walls of a closed (sealed) microchannel is achieved via a well-defined gradient in plasma intensity. The microchips comprised a microchannel positioned in-between two microelectrodes (embedded in the chip) with a variable electrode separation along the length of the channel. The channel and electrodes were 50 μm and 100 μm wide, respectively, 50 μm deep, and adjacent to the channel for a length of 18 mm. The electrode separation distance was varied linearly from 50 μm at one end of the channel to a maximum distance of 150, 300, 500, or 1000 μm to generate a gradient in helium plasma intensity. Plasma ignition was achieved at a helium flow rate of 2.5 ml/min, 8.5 kVpk-pk, and 10 kHz. It is shown that the plasma intensity decreases with increasing electrode separation and is directly related to the residual amount of BSA left after the treatment. The plasma intensity and surface protein gradient, for the different electrode gradients studied, collapse onto master curves when plotted against electrode separation. This precise spatial control is expected to enable the surface protein gradient to be tuned for a range of applications, including high-throughput screening and cell-biomolecule-biomaterial interactions. 相似文献
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Karen Jones Sally A. Sambrook Luke Pittaway Andrew Henley Heather Norbury 《Action Learning: Research and Practice》2014,11(2):131-166
This paper presents research with small- and medium-sized enterprise (SME) owners who have participated in a leadership development programme. The primary focus of this paper is on learning transfer and factors affecting it, arguing that entrepreneurs must engage in ‘action’ in order to ‘learn’ and that under certain conditions they may transfer learning to their firm. This paper draws on data from 19 focus groups undertaken from 2010 to 2012, involving 51 participants in the LEAD Wales programme. It considers the literatures exploring learning transfer and develops a conceptual framework, outlining four areas of focus for entrepreneurial learning. Utilising thematic analysis, it describes and evaluates what (actual facts and information) and how (techniques, styles of learning) participants transfer and what actions they take to improve the business and develop their people. This paper illustrates the complex mechanisms involved in this process and concludes that action learning is a method of facilitating entrepreneurial learning which is able to help address some of the problems of engagement, relevance and value that have been highlighted previously. This paper concludes that the efficacy of an entrepreneurial learning intervention in SMEs may depend on the effectiveness of learning transfer. 相似文献
75.
Systematic characterization of degas-driven flow for poly(dimethylsiloxane) microfluidic devices 总被引:1,自引:0,他引:1
Degas-driven flow is a novel phenomenon used to propel fluids in poly(dimethylsiloxane) (PDMS)-based microfluidic devices without requiring any external power. This method takes advantage of the inherently high porosity and air solubility of PDMS by removing air molecules from the bulk PDMS before initiating the flow. The dynamics of degas-driven flow are dependent on the channel and device geometries and are highly sensitive to temporal parameters. These dependencies have not been fully characterized, hindering broad use of degas-driven flow as a microfluidic pumping mechanism. Here, we characterize, for the first time, the effect of various parameters on the dynamics of degas-driven flow, including channel geometry, PDMS thickness, PDMS exposure area, vacuum degassing time, and idle time at atmospheric pressure before loading. We investigate the effect of these parameters on flow velocity as well as channel fill time for the degas-driven flow process. Using our devices, we achieved reproducible flow with a standard deviation of less than 8% for flow velocity, as well as maximum flow rates of up to 3 nL∕s and mean flow rates of approximately 1-1.5 nL∕s. Parameters such as channel surface area and PDMS chip exposure area were found to have negligible impact on degas-driven flow dynamics, whereas channel cross-sectional area, degas time, PDMS thickness, and idle time were found to have a larger impact. In addition, we develop a physical model that can predict mean flow velocities within 6% of experimental values and can be used as a tool for future design of PDMS-based microfluidic devices that utilize degas-driven flow. 相似文献
76.
In this study the authors analyze 548 secondary social science textbooks to examine the extent to which multiculturalism-related content appears over time and around the world. Findings suggest significant global increases in textbook depictions of minority rights and groups experiencing discrimination over time and in many regions. 相似文献
77.
Leslie R. Bacon 《Journal of The Franklin Institute》1935,219(5):655-656
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Comparison of Knowledge and Attitudes Using Computer-based and Face-to-Face Personal Hygiene Training Methods in Food Processing Facilities 总被引:1,自引:1,他引:0
Ginger D. Fenton Luke F. LaBorde Rama B. Radhakrishna J. Lynne Brown Catherine N. Cutter 《Journal of Food Science Education》2006,5(3):45-50
ABSTRACT: Computer-based training is increasingly favored by food companies for training workers due to convenience, self-pacing ability, and ease of use. The objectives of this study were to determine if personal hygiene training, offered through a computer-based method, is as effective as a face-to-face method in knowledge acquisition and improved attitude toward food safety. Employees from four food processing facilities ( n = 94) were randomly assigned to a control group, a face-to-face training group, or a computer-based training group. Evaluation instruments consisted of a pretest and a posttest to measure knowledge gain, a step scale to measure attitude after training and retrospectively before training, and a brief set of interview questions. Results for both treatments and the control group indicated increases in knowledge. Analysis of the posttest scores, when controlling for the pretest scores, indicated the difference was significant ( P ≤ 0.05); however, post hoc analysis did not indicate which treatment was superior. There was a significant increase in attitude scores for both groups using paired t -tests, although the difference between groups was not significant when controlling for attitude scores before training. Issues that may limit application of the technology used in this study include low literacy and language barriers among employees, and time constraints within companies. These and other variables should be taken into account in future research studies addressing comparisons of training methods. This study is the first to demonstrate the effectiveness of computer-based training aimed at food handlers who work in food processing establishments. 相似文献